Dumplings Over a Potato and Mushroom Stew

Name: Dumplings Over a Potato and Mushroom Stew
Ingredients: Scant 1 cup (200 ml) kefir (or ⅔ cup/150 ml yogurt mixed with with 3½ Tbsp. water); ½ ounce (15 g) fresh yeast, or 2¼ tsp. (7 g) active-dry yeast; 1 Tbsp. brown sugar; 1 egg, lightly beaten; 3¾ cups (450 g) all-purpose flour (or 3 cups/350 g all-purpose flour plus a scant 1 cup/100 g whole wheat or spelt flour), plus more to dust; A little vegetable oil; 3½ Tbsp (50 g) clarified butter or unsalted butter, melted; Generous 2 cups (500 ml) hot vegetable stock or water; 1¾ ounces (50 g) dried mushrooms; 4 Tbsp. vegetable oil; Pat of unsalted butter; 2 onions, thickly sliced; 14 ounces (400 g) cremini (baby bella) mushrooms; 1 pound 2 ounces (500 g) potatoes, scrubbed but unpeeled, cut in wedges; 2 large garlic cloves, roughly chopped; Black or white pepper